When i first turn on my ac it just started making a loud grinding noise when i turn it on. Any ideas on what may be causing this. Any info is appreciated

 

Kinda like a loud grind/clunk? Mine's done that since it was new...doesn't always do it, just every now and then...I've wondered the same thing myself. Since I could never repeat it on a consistent basis, I never bothered taking it in.

 

Like a quick, loud grunt? Mine has done it every once in a while since new.

 

my jeep's heater does that, it is caused by leaves and sticks falling into the fan.

 

Mine does that too. I think it is the fan belt slipping when the clutch engages, but I haven't opened the hood to see since it did it when I test drove a few trucks while looking for mine.

 

Same here.I'd like to know what it is for sure though.

 

i get a 'thunk' from somewhere in the bowels of the dash... or maybe it's out there at the compressor...

greg

 

The clunk sound (grunt sound)is when liquid refrigerant gets in the compressor. It will happen every now and then. No biggy.

 

funny... been noticing the same thing the past couple days... start it up, and thunk... pretty loud actually.. first time I thought I blew a refrigerant hose or something ... happened twice in the past week.

 

Mine makes a hell of a sound when the compressor kicks in for the first time of the day. I don't think it's anything to be concerned about.

 

My 04 did that a lot. Just had the ac compressor replaced last week. It hasnt made the noise yet.

 

My 07 (5.9) does it too, just like "rbox" said.

 

My AC was low on gas when i bought it last october. i finally got around to blasting some in the other day and the ac blew COOOLDDDD. the next day i went out lit up the monster turned on the ac and i thought i tore something up when mine made the noise, scared the crap out of me . the beast is runnin good the ac is blowin cold and the noise has occured at least three more times with varying degrees of god-awfulness. its kindof wierd how several of us has noticed this noise at the same time of year. hopefully someone that knows why will stumble our posts and educate us.

 

Mine does it every-so-often as well....only on the first time I turn it on for the day. I`m not sure what it is , and like others , I`ve not bothered having it looked at because it won`t do it ALL the time , and I know it WON`T do it for the dealer....or they`ll tell me it`s caused by the lift/programmer/tires/etc...

 

Sounds like the system is over charged to me!
Take it to a shop with good recovery equipment and see how much comes out and then put the proper amount back in.
More is not better in air conditioning.
In a nut shell you cant compress a liquid and when a system is over charged that is what the compressor is trying to do and of course will make a lot of noise.
Not normal and will fail in time